CHAIN-REACTIONS LINKING ACORNS TO GYPSY-MOTH OUTBREAKS AND LYME-DISEASE RISK

In eastern U.S. oak forests, defoliation by gypsy moths and the risk o f Lyme disease are determined by interactions among acorns, white-foot ed mice, moths, deer, and ticks. Experimental removal of mice, which e at moth pupae, demonstrated that moth outbreaks are caused by reductio ns in mouse density that occur when there are no acorns. Experimental acorn addition increased mouse density. Acorn addition also increased densities of black-legged ticks, evidently by attracting deer, which a re key tick hosts. Mice are primarily responsible for infecting ticks with the Lyme disease agent. The results have important implications f or predicting and managing forest health and human health.